MANILA, Philippines?An inmate at the Quezon City Jail pedals furiously on a stationary bike, beads of sweat trickling like fat tears down his back.

But he?s not only out to lose those extra pounds. He wants to help save on electricity consumption in the congested jail that has been his home for the past two years.

Each session on the stationary bike is equal to electric power saved on a battery attached to the bike, which the jail can use to power electric fans and light bulbs. It can even heat water for morning coffee.

The Bureau of Jail Management and Penology (BJMP) has yet to give the contraption a catchy name, but it has caught the interest of both inmates and jail guards after they saw how two electric bulbs lit up after just two minutes of intense pedaling.

Today, the BJMP?s ?Kuryente Mula sa Pawis? project aims to make use of the inmates? ?potential energy? by encouraging them to sweat it out on the bikes?and generate electricity on the side.

Dual purpose

?Biking serves a dual purpose for us here. The inmates can exercise and shed a few pounds. At the same time, the exercise generates electricity that they themselves use,? said BJMP-National Capital Region director Chief Supt. Serafin Baretto Jr.

The jail official said that with the device, they hope to bring down the electricity bill of the cramped Quezon City Jail, which houses more than 3,000 inmates.

For the project, each of the jail?s eight dormitories will get its own bike and battery, which costs P10,000 a unit.

?Our electricity bill amounting to P607,000 was reduced to P315,000 after we cut down on the use of appliances. With this gadget, we hope to be able to power up simple appliances, especially water heaters that we use for the inmates? morning coffee,? said jail warden Supt. Nestor Velasquez.

The contraption?a stationary bike supported by scrap metal collected from a junk shop, a car battery and a light bulb to demonstrate the effect?is the brainchild of a jail guard who once worked as a car mechanic.

Untapped energy

JO3 Roderick Siena, the man behind the invention, said the device works like a big dynamo that makes use of the inmates? potential energy that is largely unused as they spend time behind bars.

?I thought that since the inmates go to the gym to work out, why not use this energy in a more productive way,? he told Inquirer.

Each battery can be charged in two to three hours of pedaling on the stationary bike.

?This is one solution we came up with regarding the problem of lack of electricity, a big electricity bill and global warming caused by harmful emissions. The only emission here comes from the sweat of inmates,? he laughed.

?Two to five minutes of pedaling by an inmate is enough, then someone can replace him to charge the battery. The device stops automatically once the battery is fully charged.?

It would take around 100 inmates to fully charge the battery in three hours, Siena said.

Each battery can hold up to eight hours worth of battery life and can power up to 10 light bulbs.

It can also power up an electric fan and four light bulbs at the same time.

Inspiration

The inspiration for the contraption came about after Siena took an advance course at the Jail National Training Institute, where he saw how a wind turbine could generate electricity.

?I thought, why not try it using a bike?? Siena said.

He added that the idea was not new, but it had not been utilized in practical applications.

In a demonstration at the Quezon City jail, BJMP officials showed how the bike can not only charge the battery but also directly provide electricity to a water heater or two light bulbs.

Bills reduced

Velasquez said they still have to find out how much electricity they can save.

?We still have to see its effects on our electric bill. But hopefully, we can reduce the bill and help in the government?s austerity efforts,? the jail warden added.

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